title: Antioxidant and antimicrobial effects of phenolic compounds extracts of Northeast Portugal honey.
abstract: Phenolic compounds of dark and clear honeys from Trás-os-Montes of Portugal were extracted with Amberlite XAD-2 and evaluated for their antioxidant and antimicrobial activities. The antioxidant effect was studied using the in vitro test capacity of scavenge the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical and of reducing power of iron (III)/ferricyanide complex. The antimicrobial activity was screened using three Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, Staphylococcus lentus) and three Gram-negative bacteria (Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli). The results obtained from the partial identification of honey phenolic compounds by high-performance liquid chromatography with a diode array detector showed that p-hydroxibenzoic acid, cinnamic acid, naringenin, pinocembrin and chrysin are the phenolic compounds present in most of the samples analyzed. Antioxidant potential was dependent of honey extract concentration and the results showed that dark honey phenolic compounds had higher activity than the obtained from clear honey. In the biological assays, results showed that S. aureus were the most sensitive microrganisms and B. subtilis, S. lentus, K. pneumoniae and E. coli were each moderately sensitive to the antimicrobial activity of honey extracts. Nevertheless, no antimicrobial activity was observed in the test with P. aeruginosa.
authors.affiliation: Escola Superior Agrária de Bragança, Instituto Politécnico de Bragança, Quinta de Santa Apolónia, Apartado 1172, 5301-855 Bragança, Portugal. leticia@ipb.pt
authors.forename: Letícia
authors.initials: L
authors.lastname: Estevinho
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Pereira
authors.forename: Leandro
authors.initials: L
authors.lastname: Moreira
authors.forename: Luís G
authors.initials: LG
authors.lastname: Dias
authors.forename: Ermelinda
authors.initials: E
authors.lastname: Pereira
mesh_terms: D000890:Anti-Infective Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000494:pharmacology; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006722:Honey / Q000032:analysis*; D007202:Indicators and Reagents; D008826:Microbial Sensitivity Tests; D010084:Oxidation-Reduction; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology*; D010851:Picrates / Q000737:chemistry; D011174:Portugal; D012015:Reference Standards
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D007202:Indicators and Reagents; D010636:Phenols; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl